Answer:
mean=102
variance=15.3
standard deviation=3.91
Step-by-step explanation:
The data depict the binomial distribution because the outcome can be categorize into one of two categories that are American who favors and American who don't favor spending Govt. money to develop alternative sources of fuel for automobiles. The trial are independent and repeated 120 times. The probability of success is American who favors that is 85%.
The mean of binomial distribution is
mean=np
Here n=120 and p=0.85
Mean for the number who favor government spending for alternative fuels
mean=120*0.85=102
The variance of binomial distribution is
variance=npq
n=120, p=0.85 and q=1-p=1-0.85=0.15
The variance for the number who favor government spending for alternative fuels
Variance=120*0.85*0.15=15.3
The standard deviation for the number who favor government spending for alternative fuels can be found by taking the square root of variance
Standard deviation=√variance=√15.3
Rounding the value of standard deviation to two decimal places
Standard deviation=3.91
The mean, variance, and standard deviation for the number who favor government spending for alternative fuels are 102, 15.3 and 3.91 respectively.
